膨胀尾管悬挂器膨胀力有限元计算与试验研究

膨胀尾管悬挂器通过膨胀锥在本体内运动使其发生径向变形,依靠变形后本体与上层套管间的摩擦力,使膨胀悬挂器固定于上层套管实现尾管坐挂功能。膨胀力是膨胀锥驱动本体变形的关键、也是膨胀尾管悬挂器设计、现场施工的重要参数。采用LS-DYNA对影响膨胀力的多种因素进行研究,得到膨胀锥角、膨胀锥与本体间摩擦、膨胀本体结构对膨胀力的影响规律,并通过膨胀试验、金相观察进行验证分析。数据表明该方法能够较为准确的计算本体膨胀所需要的膨胀力及膨胀变形过程中本体的应力、应变。     

膨胀悬挂器本体膨胀性能试验研究

膨胀悬挂器依靠硫化橡胶的本体膨胀发生塑性变形,并与上层套管形成摩擦力悬挂尾管,橡胶起到密封和增大摩擦力的作用。悬挂较重的尾管需要增加本体长度,导致悬挂器整体结构增加,增大了悬挂器入井和施工风险。针对该问题优化本体设计,在本体外壁镶嵌金属块并硫化橡胶,通过膨胀试验验证了该方法的可行性,为掌握本体膨胀后与上层套管的接触应力,采用应力测试方法对本体膨胀过程中上层套管的应变进行了测量并计算得到接触应力,试验数据表明膨胀悬挂器经过结构优化在保证悬挂、密封性能的前提下使膨胀本体缩短,从而提高了现场施工的可靠性。     

膨胀悬挂器力学性能分析及试验研究

采用解析方法、有限元方法对影响悬挂器膨胀力的关键技术因素进行研究,得到了膨胀锥结构、本体材料等因素对膨胀力的影响规律。针对膨胀悬挂器实际工作状态,对膨胀本体在上层套管内膨胀进行了计算与试验研究,得到膨胀力、悬挂力与本体结构的关系。试验表明所采用的计算、试验方法能够较为精确的计算本体发生塑性变形所需要的膨胀力及膨胀后形成的悬挂力,研究成果为提高膨胀尾管悬挂器性能与整体结构优化设计提供了依据。     

膨胀悬挂器本体管材性能研究

要膨胀悬挂器通过膨胀金属本体与上层套管形成摩擦力悬挂尾管,本体管材的选取对悬挂器膨胀、悬挂性能参数有直接影响,为此采用有限元方法对本体膨胀过程进行计算,得到本体膨胀前后结构参数变化及膨胀力大小,并通过与膨胀试验得到的数据进行对比分析,验证了计算的可靠性。为确定本体膨胀前后强度变化,分别选取膨胀前、膨胀后样块进行拉伸试验,得到材料屈服、抗拉强度。数据表明的所选用的管材在膨胀后屈服强度、抗拉强度分别增大72.6%、7.94%。通过研究掌握了膨胀管材膨胀前后的力学、结构性能参数变化,为悬挂器结构设计、现场作业提供了参考依据。     

悬挂器旋转机构设计与试验研究

膨胀悬挂器通过旋转机构带动尾管转动提高固井质量、解决尾管入井遇阻问题,旋转机构需要传递大扭矩、具有高可靠性,是膨胀悬挂器研制的关键和技术难点。采用键槽传动机构实现旋转,通过扭矩套筒上的传动键与尾管套筒内壁的键槽配合传动扭矩,使用3D打印技术验证了机构的可行性,并利用ABAQUS有限元软件对旋转机构的强度进行了计算,得到扭矩应力关系曲线。在此基础上研制出旋转机构,通过扭矩测试试验和现场应用验证了其可靠性,数据表明所研制的旋转机构扭矩达到15000N·m,能够满足现场使用要求。     

尾管悬挂固井中钻杆接头伸长量计算模型建立

尾管悬挂固井作业过程中,钻杆受到多种载荷联合作用产生轴向变形;若注水泥施工步骤前的钻杆上提距离过短,会导致钻杆和尾管悬挂器在后续作业时重新扣合,使得起钻时悬挂器无法顺利脱手造成卡钻。通过对直井尾管固井施工过程中钻杆受载情况的分析,并基于钻杆接头与钻杆本体存在结构差异这一特点,提出了一种综合考虑结构场、温度场、压力场等因素的钻杆接头最大伸长量工程计算模型。运用该模型可以对尾管固井过程中钻杆的伸长量进行更加准确的分析计算,尽量减少卡钻事故。通过分析得知,静止状态下钻杆的轴向伸长量是最大的;对钻杆接头伸长量影响最大的因素是温度场,影响最小的因素是压力场,且温度对钻杆接头的影响要比对同尺寸的管柱的影响略小。     

尾管悬挂器在南堡油田定向井中的应用分析

研究复杂井况下尾管悬挂工艺,提高尾管悬挂器应用成功率。介绍冀东油田南堡区块常用液压尾管悬挂器的主要结构原理和应用该型悬挂器的南堡油田定向井的典型井况特点,结合该型悬挂器的结构原理和南堡油田定向井典型井况特点,分析南堡油田应用该型悬挂器的风险,并针对这些风险提出相应的技术措施。对2007—2018年间南堡油田应用该型悬挂器的情况进行总体技术分析和总结,得出这些技术措施对该井况具有适应性并具有推广意义。     

具有双防退功能的封隔器技术研究与应用

针对常规尾管顶部封隔器在尾管固井作业中所表现出来的环空封隔压力低,安全可靠性较差等问题,研制了带有组合式防退锁紧机构的单胶筒尾管顶部封隔器。封隔器将防退卡瓦与双面卡簧两种防退锁紧机构组合在一起,有效解决了胶筒在坐封后的回缩问题,保证了密封效果。同时封隔器胶筒采用了一体式设计,两侧为组合式防突环,可在封隔器坐封时膨胀,形成密闭空间,防止胶筒在高压作用下发生轴向窜动,进一步提高了封隔器封压能力。该型封隔器在完成样机试制后,进行了一系列地面性能试验,并在现场进行了现场应用,取得了良好的应用效果。     

液化气罐车用安全阀及其带压堵漏器

介绍了一种新型的液化气罐车用安全阀及其带压堵漏器的性能和工作原理。当安全阀发生泄漏时,带压堵漏器可方便快速地安装在安全阀上,达到迅速堵漏、防止事故蔓延扩大的目的。     

工程机械气顶油行车制动系统的结构改进

正1.气顶油行车制动系统目前压路机、装载机、平地机等工程机械大都采用气顶油行车制动系统。该系统主要由发动机1、空压机2、安全阀3、油水分离器4、储气筒5、脚踏制动阀6、气顶油加力泵7、制动钳8组成,如图1所示。储气筒5上安装有安全阀3,当储气简5储气压力达到安全阀3设定压力值后,安全阀3向外排气,以保持设定压力值。制动时,压缩空气从储气筒5经脚踏制动阀6到达气顶油加力泵7。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...